Battle of Jutland - The Outcome - British Self-critique - Ammunition Handling

Ammunition Handling

British and German propellant charges differed in packaging, handling, and chemistry. The British propellant was of two types, MK1 and MD. The Mark 1 cordite had a formula of 37% nitrocellulose, 58% nitroglycerine, and 5% petroleum jelly. It was a good propellant but burned hot and caused an erosion problem in gun barrels. The petroleum jelly served as both a lubricant and a stabilizer. Cordite MD was developed to reduce barrel wear, its formula being 65% nitrocellulose, 30% nitroglycerine, and 5% petroleum jelly. While cordite MD solved the gun-barrel erosion issue, it did nothing to improve its storage properties, which were poor. Cordite was very sensitive to variations of temperature, and acid propagation/cordite deterioration would take place at a very rapid rate. Cordite MD also shed micro-dust particles of nitrocellulose and iron pyrite. While cordite propellant was manageable, it required a vigilant gunnery officer, strict cordite lot control, and frequent testing of the cordite lots in the ships' magazines.

British cordite propellant (when uncased and exposed in the silk bag) tended to burn violently, causing uncontrollable "flash fires" when ignited by nearby shell hits. In 1945, a test was conducted by the U.S.N. Bureau of Ordnance (Bulletin of Ordnance Information, No.245, pp. 54–60) testing the sensitivity of Cordite to then-current U.S. Naval propellant powders against a measurable and repeatable flash source. It found that cordite would ignite at 530 mm/22" from the flash and the current U.S. powder at 120 mm,/5" the U.S. flashless powder at 25 mm./1" This meant that about 75 times the propellant would immediately ignite when exposed to flash, as compared to the U.S. powder. British ships had inadequate protection against these flash fires. German propellant (RP C/12, handled in brass cartridge cases) was less vulnerable and less volatile in composition. German propellants show that they were not that different in composition from cordite—with one major exception: centralite. This was symmetrical Diethyl Diphenyl Urea, which served as a stabilizer that was superior to the petroleum jelly used in British practice. It stored better and burned but did not explode. Stored and used in brass cases, it proved much less sensitive to flash. RP C/12 – 64.13% nitrocellulose, 29.77% nitroglycerine, 5.75% centralite, 0.25% magnesium oxide and 0.10% graphite.

The Royal Navy Battle Cruiser Fleet had also emphasized speed in ammunition handling over established safety protocol. In practice drills, cordite could not be supplied to the guns rapidly enough through the hoists and hatches. To bring up the propellant in good time to load for the next broadside, many safety doors were kept open that should have been shut to safeguard against flash fires. Bags of cordite were also stocked and kept locally, creating a total breakdown of safety design features. By staging charges in the chambers between the gun turret and magazine, the Royal Navy enhanced their rate of fire but left their ships vulnerable to chain reaction ammunition fires and magazine explosions. This 'bad safety habit' carried over into real battle practices. Furthermore, the doctrine of a high rate of fire also led to the decision in 1913 to increase the supply of shells and cordite held on the British ships by 50%, for fear of running out of ammunition. When this exceeded the capacity of the ships' magazines, cordite was stored in insecure places.

The British cordite charges were stored two silk bags to a metal cylindrical container, with a 16-oz gunpowder igniter charge, which was covered with a thick paper wad, four charges being used on each projectile. The gun crews were removing the charges from their containers and removing the paper covering over the gunpowder igniter charges. The effect of having eight loads at the ready was to have 4 short tons (3,600 kg) of exposed explosive, with each charge leaking small amounts of gunpowder from the igniter bags. In effect, the gun crews had laid an explosive train from the turret to the magazines, and one shell hit to a battlecruiser turret was enough to end a ship.

A diving expedition during the summer of 2003 provided corroboration of this practice. It examined the wrecks of Invincible, Queen Mary, Defence, and Lützow to investigate the cause of the British ships' tendency to suffer from internal explosions. From this evidence, a major part of the blame may be laid on lax handling of the cordite propellant for the shells of the main guns. The wreck of the Queen Mary revealed cordite containers stacked in the working chamber of the X turret instead of the magazine.

There was a further difference in the propellant itself. While the German RP C/12 burned when exposed to fire, it did not explode, as opposed to cordite. RP C/12 was extensively studied by the British and, after World War I, would form the basis of the later Cordite SC.

The memoirs of Alexander Grant, Gunner on Lion, suggest that some British officers were aware of the dangers of careless handling of cordite:

"With the introduction of cordite to replace powder for firing guns, regulations regarding the necessary precautions for handling explosives became unconsciously considerably relaxed, even I regret to say, to a dangerous degree throughout the Service. The gradual lapse in the regulations on board ship seemed to be due to two factors. First, cordite is a much safer explosive to handle than gun-powder. Second, but more important, the altered construction of the magazines on board led to a feeling of false security....The iron or steel deck, the disappearance of the wood lining, the electric lights fitted inside, the steel doors, open because there was now no chute for passing cartridges out; all this gave officers and men a comparative easiness of mind regarding the precautions necessary with explosive material".

Grant had already introduced measures onboard Lion to limit the number of cartridges kept outside the magazine and to ensure doors were kept closed, probably contributing to her survival.

On 5 June 1916, the First Lord of the Admiralty advised Cabinet Members that the three battlecruisers had been lost due to unsafe cordite management.

On 22 November 1916, following detailed interviews of the survivors of the destroyed battlecruisers, the Third Sea Lord, Rear Admiral Tudor, issued a report detailing the stacking of charges by the gun crews in the handling rooms to speed up loading of the guns.

After the battle, the B.C.F. Gunnery Committee issued a report (at the command of Admiral David Beatty) advocating immediate changes in flash protection and charge handling. It reported, among other things, that:

• Some vent plates in magazines allowed flash into the magazines and should be retro-fitted to a new standard.
• Bulkheads in HMS Lion's magazine showed buckling from fire under pressure (overpressure) – despite being flooded and therefore supported by water pressure – and must be made stronger.
• Doors opening inward to magazines were an extreme danger.
• Current designs of turrets could not eliminate flash from shell bursts in the turret from reaching the handling rooms.
• Ignition pads must not be attached to charges but instead be placed just before ramming.
• Better methods must be found for safe storage of ready charges than the current method.
• Some method for rapidly drowning charges already in the handling path must be devised.
• Handling scuttles (special flash-proof fittings for moving propellant charges through ship's bulkheads), designed to handle overpressure, must be fitted.

The United States Navy in 1939 had quantities of Cordite N, a Canadian propellant that was much improved, yet its Bureau of Ordnance objected strongly to its use onboard U.S. warships, considering it unsuitable as a naval propellant due to its inclusion of nitroglycerin.